Alert archive / Minnesota / Mesoscale Discussions in 2012

Mesoscale Discussion 1540

July 22, 20129 counties in Iowa; 14 counties in Minnesota; 7 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jul 22, 2012, 2:32 PM CDT for 9 counties in Iowa; 14 counties in Minnesota; 7 counties in Wisconsin. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued
Jul 22, 2012, 2:32 PM CDT (19:32 UTC)
Expired
Jul 22, 2012, 4:00 PM CDT
In force
88 min
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 30 counties

Allamakee County, IA, Chickasaw County, IA, Clayton County, IA, Fayette County, IA, Howard County, IA, Mitchell County, IA, Winnebago County, IA, Winneshiek County, IA, Worth County, IA, Blue Earth County, MN, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Houston County, MN, Le Sueur County, MN, Mower County, MN, Olmsted County, MN, Rice County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Winona County, MN, Crawford County, WI, Grant County, WI, Iowa County, WI, La Crosse County, WI, Richland County, WI, Sauk County, WI, Vernon County, WI

The radar

The La Crosse radar (KARX), 90 km from the middle of the area, began a volume at 19:31 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 7.5 hours before the alert went out and 174 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2012-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 130 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2012-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 161 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
130 J/kg
Mixed-layer CIN
-274 J/kg
Mixed-layer LCL
1395 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
161 m²/s²
0-3 km storm-relative helicity
194 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 10:51 PM CDTMesoscale DiscussionSPCLincoln, Lyon, Murray, Nobles, Pipestone, Redwood and 2 more54 min
Jul 22, 1:40 PM CDTMesoscale DiscussionSPCBecker, Beltrami, Clay, Clearwater, Hubbard, Koochiching and 7 more95 min
Jul 22, 3:25 PM CDTSevere Thunderstorm WatchSPCAitkin, Becker, Beltrami, Carlton, Cass, Clay and 18 more6 hr
Jul 22, 5:45 PM CDTSevere Thunderstorm WatchSPCBig Stone, Traverse4 hr
Jul 22, 6:55 PM CDTMesoscale DiscussionSPCBecker, Beltrami, Cass, Clay, Clearwater, Hubbard and 11 more95 min

Nearby

Mesoscale Discussions in Minnesota, 2012Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Wisconsin, 2012Every mesoscale discussion in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.